function showPageData(data){
	alert("hello world");	
	 var trends_dom = document.createElement('div');
	 trends_dom.style.background = '#36b';
    trends_dom.style.color = '#fff';
    trends_dom.style.padding = '10px';
    trends_dom.style.position = 'relative';
    trends_dom.style.zIndex = '123456';
    trends_dom.style.font = '14px Arial';
	document.body.insertBefore(trends_dom, document.body.firstChild);
}

console.log(chrome.extension);
chrome.extension.onRequest.addListener(
  function(request, sender, sendResponse) {
    console.log(sender.tab ?
                "from a content script:" + sender.tab.url :
                "from the extension");
    if (request.greeting == "hello"){
      showPageData(null);
	  sendResponse({farewell: "goodbye"});
	  }
    else{
      sendResponse({}); // snub them.
	  }
  });
